Broth microdilution is a method used to test the susceptibility of

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antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and preventio ...

. It is the most commonly used method to perform this test in the

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Process

During testing, multiple microtiter plates are filled with a certain broth, according to the needs of target bacteria. Varying concentrations of the antibiotics and the bacteria to be tested are then added to the plate. The plate is then placed into a non-

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and incubated at thirty-seven degrees

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for sixteen to twenty hours. Following the allotted time, the plate is removed and checked for bacterial growth. If the broth became cloudy or a layer of cells formed at the bottom, then bacterial growth has occurred. The results of the broth microdilution method are reported in Minimum Inhibitory Concentration (MIC), or the lowest concentration of antibiotics that stopped bacterial expansion.

Advantages

The broth microdilution method can be used to test the susceptibility of microorganisms to multiple antibiotics at once. Broth microdilution is also highly accurate. The accuracy of its results are comparable to

agar dilution Agar dilution is one of two methods (along with Broth Dilution) used by researchers to determine the Minimum Inhibitory Concentration (MIC) of antibiotics. It is the dilution method most frequently used to test the effectiveness of new antibiotics w ...

, the

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of susceptibility testing. Other advantages include the commercial availability of plates, the ease of testing and storing the plates, and the ability for the results of some tests to be read by machines.

References

{{Reflist Antimicrobial resistance